by Andrea Mandell, USA TODAY

by Andrea Mandell, USA TODAY

Onscreen and off, awards-season favorite American Hustle is a family affair.

Just weeks before the film was released, director David O. Russell invited USA TODAY into the edit room for an exclusive look at the film's final days, and proudly pointed to scenes in which his son Matthew (who inspired the director to make Silver Linings Playbook) cameos as one of Mayor Carmine Polito's (Jeremy Renner) sons.

There's another tot-sized surprise guest in the mix, too. "That's actually Jeremy Renner's baby," he says, pointing to a shot in which Renner, in politico mode, cradles a constituent's month-old infant.

How did that happen? "They brought the baby and they were hanging around with (Renner's) mother," says Russell. "I couldn't get his mother to be in the scene. But I said, 'Why don't you put the baby in the scene right now?' "

Bradley Cooper even inserted a deeply personal tick of his late father's into his erratic FBI agent, Richie DiMaso. "He found this thing where he chewed his tongue, which his late father did," says Russell, which became DiMaso's tell when he was losing control.

Did the director ever try to coax Cooper's mom in a shot? "She was not in Boston, she was in Philly during that time," says Cooper. "But on Silver Linings, there was a half a second, well at least Bob (De Niro) and I pitched her playing my mom in the movie. Luckily, thank god he said 'No, Jacki Weaver's going to do it.'"